105 ILCS 5/34-76
When a warrant issued for the wages of a teacher or other employee is presented to the school treasurer and is not paid for want of funds, the school treasurer shall endorse it over his signature, "not paid for want of funds," with the date of presentation, and shall make and keep a record of such endorsement. The warrant shall thereafter bear interest at the rate of 7% per annum if issued before January 1, 1972 or at the rate of 6% per annum if issued after January 1, 1972, until the school treasurer notifies the president of the board in writing that he has funds to pay it. The school treasurer shall make and keep a record of such notices and hold the funds necessary to pay the warrant until it is presented. The warrant shall draw no interest after notice is given to the president of the board.
105 ILCS 5/34-76